More serious than polio, really?
Paralysis is often permanent, although total or partial recovery can occur through compensation by muscles not affected. Weakness or paralysis present 12 months after onset, which occurs in two-thirds of patients with paralysis, is usually
The case fatality ratio for paralytic polio is generally 2% to 5% among children and up to 15% to 30% among adolescents and adults. It increases to 25% to 75% with bulbar involvement.
https://www.cdc.gov/vaccines/pubs/pinkbook/polio.html